Improvement in tubular boilers



G- H- POND. Tubular Boilerl Platented March 5,1878.

n. Ress L UNITED STATES PATENT OEEICE.

GOLDSBURY H. POND,

O'F NEW YORK, N. Y.

IMPROVEMENT IIN TUBULAR BOILERS.

Specification forming part of Letters Patent N o. 200,873, dated March5, 1878; application led June 12, 1877.

To all 'whom 'it may concern:

Beit known that I, GoLDsBURY HARDEN POND, of the city, county, and Stateof New York, have invented a new and useful Improvement in TubularBoilers, which improvement is fullv set forth in the followingspeccation, reference being had to the accompanying drawings, in whichFigure 1 is a vertical sectional view. Fig. 2 is a transverse sectionalView, and Fig. 3 is an end view.

The object of my invention is to produce a cheap but strong and durabletubular boiler, light in weight, simple in construction, without seamsthat have to be riveted, as in the ordinary boiler, or heads that haveto be turned, making a tubular boiler with four circular heads, two ateach end of the boiler, with a space between them. The two double headsare fastened together with tubes instead of bolts, screws, or rivets',and are of immense strength and great eiciency.

I make my tubular boiler by first casting, of malleable cast-steel orother metal, two perforated disks of the size required to hold thetubes. A surrounding rim of the same metal is cast on two of the disks,to inclose a space as large as deemed requisite for the size of theboiler, for steam and water space between the perforated disks and rim,as shown at A A', Fig. 1, thereby making the double heads without seams,rivets, or screws, and also without drilling the holes for the tubes. Ithen take two of these cast double heads, A A', Fig. 1,for each end ofthe boiler, and place them opposite each other, as far apart as Idesignthe length of the boiler to be, and put the irst or short set of tubes,B, Fig. 1, into the heads nearest each other on the inner sides C C.Then, with a tube-setting tool,I expand them in the usual manner,forming a shoulder in the tube on each side of the head, therebyfastening the double heads together.

The next set, or long tubes D, which are smaller than the short tubes,are put into the holes in the outside heads, and through the insideheads and the short tubes, to the opposite end of the boiler. The endsof the tubes are expanded and made tight with the tube-setting tool,forming a shoulder in each tube on each Vside of the head, making strongbraces lengthwise of the boiler, and with the short tubes they fastenthe double heads firmly together, thereby making a tubular boiler withfour circular heads of immense strength, without either rivets, bolts,or screws.

When the boiler is used vertically, or as a portable boiler, thebaflle-plate K, Fig. 2, is necessary to direct the lia-me, heat, andsmoke round and between the tubes, and round the upper heads.

L, Fig. 1, is the sheet-iron casing for the boiler, which may be linedwith brick or clay, the lower end of the casing forming the fireboximmediately under the lower heads. The upper double head is used for asteam-drum.

I claim as my invention- The combination of the double heads connectedtogether by two sets of tubes, the iretubes passing through thewater-tubes, and the diaphragm K, substantially as and for the purposeset forth.

GOLDSBURY HARDEN POND.

Witnesses:

MARY C. SAWTELLE, J. P. SAWTELLE.

